Topical glucocorticoids with improved risk-benefit ratio. Rationale of a new concept

[Recommendations when switching therapy from immunosuppressive drugs to dupilumab in patients with atopic dermatitis]

Based on new insights into the molecular pathogenesis of atopic dermatitis, a targeted anti-inflammatory therapy-dupilumab-has recently been approved as treatment alongside glucocorticoids and ciclosporin. Due to their pharmacology, neither glucocorticoids nor ciclosporin nor the off label used substances methotrexate, azathioprine and mycophenolic acid derivatives are suitable for long-term therapy. When switching therapy from small molecular substances to dupilumab, various factors should be considered. Both the specific cause of the change (ineffectiveness, adverse effects or contraindications) as well as the pharmacological conditions should be taken into account. Since there have been no specific clinical studies on this subject so far, the authors relied mainly on a literature search to draw up recommendations for practical everyday use.

Development and application of a highly efficient CRISPR-Cas9 system for genome engineering in Bacillus megaterium

Bacillus megaterium has become increasingly important for the biotechnological production of valuable compounds of industrial and pharmaceutical importance. Despite recent advances in rational strain design of B. megaterium, these studies have been largely impaired by the lack of molecular tools that are not state-of-the-art for comprehensive genome engineering approaches. In the current work, we describe the adaptation of the CRISPR-Cas9 vector pJOE8999 to enable efficient genome editing in B. megaterium. Crucial modifications comprise the exchange of promoter elements and associated ribosomal binding sites as well as the implementation of a 5-fluorouracil based counterselection system to facilitate proper plasmid curing. In addition, the functionality and performance of the new CRISPR-Cas9 vector pMOE was successfully evaluated by chromosomal disruption studies of the endogenous β-galactosidase gene (BMD_2126) and demonstrated an outstanding efficiency of 100 % based on combinatorial pheno- and genotype analyses. Furthermore, pMOE was applied for the genomic deletion of a steroid esterase gene (BMD_2256) that was identified among several other candidates as the gene encoding the esterase, which prevented accumulation of pharmaceutically important glucocorticoid esters. Recombinant expression of the bacterial chloramphenicol acetyltransferase 1 gene (cat1) in the resulting esterase deficient B. megaterium strain ultimately yielded C21-acetylated as well as novel C21-esterified derivates of cortisone.

Anti-Allergic and Anti-Inflammatory Effects of Undecane on Mast Cells and Keratinocytes

The critical roles of keratinocytes and resident mast cells in skin allergy and inflammation have been highlighted in many studies. Cyclic adenosine monophosphate (cAMP), the intracellular second messenger, has also recently emerged as a target molecule in the immune reaction underlying inflammatory skin conditions. Here, we investigated whether undecane, a naturally occurring plant compound, has anti-allergic and anti-inflammatory activities on sensitized rat basophilic leukemia (RBL-2H3) mast cells and HaCaT keratinocytes and we further explored the potential involvement of the cAMP as a molecular target for undecane. We confirmed that undecane increased intracellular cAMP levels in mast cells and keratinocytes. In sensitized mast cells, undecane inhibited degranulation and the secretion of histamine and tumor necrosis factor α (TNF-α). In addition, in sensitized keratinocytes, undecane reversed the increased levels of p38 phosphorylation, nuclear factor kappaB (NF-κB) transcriptional activity and target cytokine/chemokine genes, including thymus and activation-regulated chemokine (TARC), macrophage-derived chemokine (MDC) and interleukin-8 (IL-8). These results suggest that undecane may be useful for the prevention or treatment of skin inflammatory disorders, such as atopic dermatitis, and other allergic diseases.

Potential Therapeutic Applications of Bee Venom on Skin Disease and Its Mechanisms: A Literature Review

Skin is larger than any other organ in humans. Like other organs, various bacterial, viral, and inflammatory diseases, as well as cancer, affect the skin. Skin diseases like acne, atopic dermatitis, and psoriasis often reduce the quality of life seriously. Therefore, effective treatment of skin disorders is important despite them not being life-threatening. Conventional medicines for skin diseases include corticosteroids and antimicrobial drugs, which are effective in treating many inflammatory and infectious skin diseases; however, there are growing concerns about the side effects of these therapies, especially during long-term use in relapsing or intractable diseases. Hence, many researchers are trying to develop alternative treatments, especially from natural sources, to resolve these limitations. Bee venom (BV) is an attractive candidate because many experimental and clinical reports show that BV exhibits anti-inflammatory, anti-apoptotic, anti-fibrotic, antibacterial, antiviral, antifungal, and anticancer effects. Here, we review the therapeutic applications of BV in skin diseases, including acne, alopecia, atopic dermatitis, melanoma, morphea, photoaging, psoriasis, wounds, wrinkles, and vitiligo. Moreover, we explore the therapeutic mechanisms of BV in the treatment of skin diseases and killing effects of BV on skin disease-causing pathogens, including bacteria, fungi and viruses.

The Anti-Inflammatory Effects of Fermented Herbal Roots of Asparagus cochinchinensis in an Ovalbumin-Induced Asthma Model

Introduction: Roots of Asparagus cochinchinensis, which have pharmacologically active ingredients, have received great attention because they show good therapeutic effects for various inflammatory diseases without specific toxicity. This study investigated the anti-asthmatic effects of a butanol extract of Asparagus cochinchinensis roots that had been fermented with Weissella cibaria (BAW) and its possible underlying cholinergic regulation. Methods: Alterations of the anti-asthmatic markers and the molecular response factors were measured in an ovalbumin (OVA)-induced asthma model after treatment with BAW. Results: Treatment with BAW decreased the intracellular reactive oxygen species (ROS) production in lipopolysaccharides (LPS) activated RAW264.7 cells. The results of the animal experiments revealed lower infiltration of inflammatory cells and bronchial thickness, and a significant reduction in the number of macrophages and eosinophils, concentration of OVA-specific IgE, and expression of Th2 cytokines in the OVA + BAW treated group. In addition, a significant recovery of goblet cell hyperplasia, MMP-9 expression, and the VEGF signaling pathway was observed upon airway remodeling in the OVA + BAW treated group. Furthermore, these responses of BAW were linked to recovery of acetylcholine esterase (AChE) activity and muscarinic acetylcholine receptor (mAChR) M3 downstream signaling pathway in epithelial cells, smooth muscle cells, and afferent sensory nerves of OVA + BAW-treated mice. Conclusion: Overall, these findings are the first to provide evidence that the therapeutic effects of BAW can prevent airway inflammation and remodeling through the recovery of cholinergic regulation in structural cells and inflammatory cells of the chronic asthma model.

Effects of topical corticosteroids on cell proliferation, cell cycle progression and apoptosis: in vitro comparison on HaCaT

Topical-corticosteroids are mainly used for the treatment of inflammatory or hyperproliferative skin diseases. The in vivo assay to rank topical-corticosteroids potency, based on the skin blanching, is not adapted to compare their anti-proliferative efficacy. We have compared the antiproliferative effect of six topical-corticosteroids on a model of hyperproliferant keratinocytes (HaCaT). Betamethasone-dipropionate; clobetasol-propionate; betamethasone-valerate; desonide; hydrocortisone-butyrate and hydrocortisone-base, at different concentrations (10(-8)-10(-4)M) have been compared. HaCaT proliferation has been evaluated by MTT-assay and the mechanism of the death was evaluated by annexin V/propidium iodide staining and cell cycle phases analysis. Topical corticosteroids reduced cell growth in a dose-dependent manner. At 10(-4)M, betamethasone dipropionate was the most antiproliferative compound while hydrocortisone-butyrate was the less. Hydrocortisone-base which is usually considered as the less potent topical-corticosteroids showed a clear cytotoxic effect. Betamethasone-dipropionate and betamethasone-valerate induced more apoptosis than necrosis whereas the reverse has been observed for other topical-corticosteroids. All topical-corticosteroids, except clobetasol-propionate, arrested cell cycle mainly in G2-phase. Clobetasol-propionate arrested cell cycle in S-phase population. At 10(-8)M, topical-corticosteroids induced HaCaT proliferation. In terms of antiproliferative effect at 10(-4)M, we propose to rank topical corticosteroids as follow: betamethasone-dipropionate>desonide≥betamethasone-valerate=hydrocortisone-base=clobetasol-propionate>hydrocortisone-butyrate. This classification differs from the current ranking, based on the vasoconstrictive effect, but is more adapted for hyperproliferative disease treatment.

Nobiletin and tangeretin ameliorate scratching behavior in mice by inhibiting the action of histamine and the activation of NF-κB, AP-1 and p38

Nobiletin and tangeretin are polymethoxy flavonoids that are abundantly present in the pericarp of Citrus unshiu (family Rutaceae) and the fruit of Citrus depressa (family Rutaceae). They exhibit various biological activities, including anti-inflammatory and anti-asthmatic effects. To evaluate the anti-allergic effects of nobiletin and tangeretin, we measured their inhibitory effects in histamine- or compound 48/80-induced scratching behavioral mice. Nobiletin and tangeretin potently inhibited scratching behavior, as well as histamine-induced vascular permeability. Furthermore, they inhibited the expression of the allergic cytokines, IL-4 and TNF-α as well as the activation of their transcription factors NF-κB, AP-1 and p38 in histamine-stimulated skin tissues. They also inhibited the expression of IL-4 and TNF-α and the activation of NF-κB and c-jun in PMA-stimulated RBL-2H3 cells. Furthermore, nobiletin and tangeretin inhibited protein kinase C (PKC) activity and the IgE-induced degranulation of RBL-2H3 cells. These agents showed potent anti-histamine effect through the Magnus test when guinea pig ileum was used. Based on these results, nobiletin and tangeretin may ameliorate scratching behavioral reactions by inhibiting the action of histamine as well as the activation of the transcription factors NF-κB and AP-1 via PKC.

Inhibitory effect of Lactobacillus plantarum K-1 on passive cutaneous anaphylaxis reaction and scratching behavior in mice

Lactobacillus plantarum K-1 (LP) inhibiting AP-1 (c-Jun) and NF-κB activations was isolated from kimchi, and its inhibitory activity against scratching behavior and passive cutaneous anaphylaxis reaction in mice was investigated. Heat-inactivated LP (heated at 60°C for 30 min) potently inhibited the expression of TNF-α and IL-4 as well as the activation of their transcription factors, NF-κB and c-jun, in phorbol 12'-myristate 13'-acetate-stimulated RBL-2H3 cells. LP (1 × 10(10) CFU per mouse) showed a potent inhibition against passive cutaneous anaphylaxis reaction induced by the IgE-antigen complex in mice, inhibiting it by 87.5%. LP (1 × 10(10) CFU/mouse) inhibited histamine-induced scratching behavior by 58.9% compared to the control group. LP significantly inhibited vascular permeability induced by histamine. The inhibitory activity of LP against vascular permeability was in proportion to its inhibition against scratching behavior. LP potently inhibited histamine-induced cytokine production: it (1 × 10(10) CFU per mouse) inhibited IL-4, IL-1β, and TNF-α expression by 88.9%, 88.6%, and 98.9%, respectively. LP also inhibited IgE level increased by histamine by 85.3%. It inhibited histamine-induced the activations of their transcription factors, NF-κB and c-Jun. Based on these findings, LP may improve allergic diseases, such as anaphylaxis, atopic dermatitis, rhinitis, and pruritus by inhibiting the expression of IgE-switching cytokine IL-4 and proinflammatory cytokines IL-1β and TNF-α via NF-κB and AP-1 signaling pathways.

Topical fluticasone propionate: intervention and maintenance treatment options of atopic dermatitis based on a high therapeutic index

Fluticasone propionate (FP), a medium potent glucocorticoid (class III) of carbothioate nature with a favourable benefit/risk ratio, has emerged as a standard medication for the topical treatment of inflammatory skin disorders, in particular atopic dermatitis (AD). FP is available as a 0.05% cream and a 0.005% ointment formulation. The glucocorticoid is characterized by high lipophilicity, high affinity binding to the glucocorticoid receptor and a rapid hepatic biotransformation. Though skin blanching following topical application of FP surpasses that given with glucocorticoids of medium strength, clinical trials show a low potential of FP for local and systemic adverse effects. Even in paediatric patients with AD as well as in difficult-to-treat areas like face, eyelids and intertriginous areas, FP proved to be both effective and safe. Thus, the therapeutic effects of FP clearly outweigh the unwanted effects. Correspondingly, a therapeutic index of 2.0 can be attributed to this glucocorticoid. In this respect, topical FP does not differ from other topical glucocorticoids with increased benefit-to-risk ratio, e.g. prednicarbate, methylprednisolone aceponate and mometasone furoate. However, randomized controlled trials do not only support conventional intervention but also innovative maintenance treatment.

[New tyrosine kinase and EGFR inhibitors in cancer therapy. Cardiac and skin toxicity as relevant side effects. Part B: Skin]

Recently, inhibitors of the epidermal growth factor receptor (EGFR) and multikinase inhibitors have been successfully established in the therapy of various solid tumors. EGFR inhibitors and multikinase inhibitors are specific and selective agents that intervene with the dysfunctional regulatory processes of malignant cells. This results in a favorable safety profile and range of side effects, especially in comparison to conventional chemotherapy. The various cutaneous adverse drug reactions are considered substance class effects and are the most frequent side effects of these targeted therapies. Therapy with EGFR inhibitors is associated with acneiform rash, painful paronychia, xerosis cutis, acral fissures, hair changes, and pruritus. Treatment with tyrosin kinase inhibitors may cause hand-foot syndrome, various types of drug rash, hair loss, xerosis cutis, and pruritus. These side effects may be stigmatizing and place a huge burden on the patient's quality of life. Treatment is a challenge and best performed in interdisciplinary cooperation of dermatologists and oncologists.

Evaluation of anti-inflammatory and atrophogenic effects of glucocorticoids on reconstructed human skin

Topical glucocorticoids (GCs) are extensively used in the treatment of inflammatory skin diseases. However, their long-term use is often accompanied by severe and eventually irreversible adverse effects, with atrophy being the most important limitation. Currently, most non-clinical studies involve animal testing, so the results are not always representative of the situation in humans. The aim of this project was to establish an in vitro test protocol for the evaluation of the anti-inflammatory and atrophic potential of topically applied GCs in reconstructed human skin. Initial studies with fibroblasts and keratinocytes confirmed the anti-inflammatory and atrophogenic effects of GCs, as evidenced by decreased cytokine production and collagen mRNA expression. In non-pretreated reconstructed human skin (EpiDermFT™), the topical application of GCs for seven days strongly reduced the secretion of interleukin (IL)-6. GC-induced skin atrophy, known to appear only after prolonged treatment, was not detected by the analysis of epidermal thickness and collagen mRNA expression. However, reproducible epidermal inflammation was established for the first time in reconstructed human skin. Topical treatment with tumour necrosis factor (TNF) increased IL-6 release and strongly reduced epidermal thickness accompanied by severe parakeratosis. GC treatment of reconstructed human skin reduced IL-6 levels and completely resolved parakeratosis, leading to the normalisation of epidermal thickness. These induced inflammatory conditions mimic more closely the clinical situations in which GCs are used, and therefore appear to be more suitable for future investigations for the establishment of a human-based in vitro test protocol for evaluating wanted and unwanted GC effects.

Tanshinones isolated from the rhizome of Salvia miltiorrhiza inhibit passive cutaneous anaphylaxis reaction in mice

ETHNOPHARMACOLOGICAL RELEVANCE

The rhizome of Salvia miltiorrhiza Bunge (SM, family Labiatae), which contains tanshinones as main constituents, has been used as a cardiovascular and anti-inflammatory agent in Chinese medicine.

AIM OF THE STUDY

This study aimed to elucidate anti-allergic effects of the root of Salvia miltiorrhiza Bunge (SM, family Labiatae) and its main constituents, tanshinones, against passive cutaneous anaphylaxis (PCA) reaction.

MATERIALS AND METHODS

PCA reaction was induced by IgE-antigen complex (IAC) in ICR mice. Protein expression of IL-4 and TNF-α in rat basophilic leukemia (RBL)-2H3 cells was performed by enzyme-linked immunosorbent assay and NF-κB and c-jun (AP-1) activation assayed by immunoblot.

RESULTS

Tanshinones inhibited the PCA reaction and reduced IL-4 and TNF-α production in mice as well as in IAC-stimulated RBL-2H3 cells. Tanshinones also inhibited NF-κB and AP-1 activation in RBL-2H3 cells stimulated with IAC. Among tested tanshinones, tanshinone I exhibited the most potent inhibition, followed by 15,16-dihydrotanshinone I, tanshinone IIA and cryptotanshinone.

CONCLUSIONS

SM and tanshinones may ameliorate the PCA reaction by inhibiting the allergic cytokines IL-4 and TNF-α via NF-κB and AP-1 pathways.

Qualitative and quantitative assessment of the benefit-risk ratio of medium potency topical corticosteroids in vitro and in vivo: characterisation of drugs with an increased benefit-risk ratio

Corticosteroids are widely used for the treatment of inflammatory skin disorders. However, systemic and local adverse drug reactions, especially skin atrophy, are potential complications that limit their use. Several attempts have been made to increase the safety of topical corticosteroid treatment, including new application schedules, special vehicles and new agents. In particular, the group of hydrocortisone and prednisolone double esters, with prednicarbate as the first and most often prescribed representative, seem to be equipotent alternatives to the gold standard betamethasone 17-valerate with respect to anti-inflammatory activity. At the same time, these new agents induce less skin atrophy, which may result from a unique skin metabolism and a specific influence on the cytokine network in the epidermis and dermis. On the basis of these effects, a new approach to in vitro quantification of the benefit-risk ratio has been developed. As already suggested by investigations in human volunteers, the benefit-risk ratio of the new compounds appears to be increased. Therefore, recent research has focused on drugs that selectively modulate cytokine release.

Carriers in the topical treatment of skin disease

Topical drug application is less prone to severe systemic side-effects than systemic application. Starting with the liposomes, various types of nanosized and microsized drug carriers have been developed to increase the notoriously low penetration of active agents into the skin, which limits not only the topical therapy of skin disease but also transdermal therapy. Today, liposome- and microsponge-based preparations are approved for dermatomycosis, acne and actinic keratosis. Under investigation are drug carriers such as lipid nanoparticles, polymeric particles, dendrimers, and dendritic-core multi-shell nanotransporters. According to the rapidly increasing research in this field, both in academia and industry, a breakthrough appears likely, once stability problems (nanoparticles) and safety concerns (dendrimers) are overcome. Technical approaches and results of in vitro, ex vivo and in vivo testing are described, taking into account pharmacokinetic, efficacy and safety aspects.

Cushing's Syndrome Induced by Misuse of Moderate- to High-Potency Topical Corticosteroids

Objective:

To report a case of Cushing's syndrome caused by continuous use of moderate- to high-potency topical corticosteroids over several months.

Case Summary:

An 11-month-old patient with atopic dermatitis received uninterrupted treatment with moderate- to high-potency topical corticosteroids. He presented with several food allergies and was admitted to the hospital after atopic dermatitis worsened. Signs of growth retardation, which had begun at 6 months of age, were also noted during the child's hospital stay. An endocrinologist concluded that a lower-than-normal bone density scan and growth retardation on both weight and growth curves were due to suppression of the hypothalamic–pituitary–adrenal (HPA) axis and a multifactorial failure to thrive.

Discussion:

This is a case of an infant overexposed to topical corticosteroid treatment who developed Cushing's syndrome within a few months. Local treatment of atopic dermatitis is classically based on the use of topical corticosteroids in combination with an emollient or other drugs. To limit local and general damaging effects, the choice of topical corticosteroid must be made in terms of patient age, severity and site of the rash, and the extent of skin involvement. Several factors influence the systemic absorption of topical corticosteroids. While our literature review indicated the possibility of a multifactorial origin of the child's growth retardation, the use of topical corticosteroids was shown to have contributed to suppression of the HPA axis. Application of the Naranjo probability scale indicated a probable relationship between the continuous and sustained administration of topical corticosteroids over several months and suppression of the HPA axis. Although topical corticosteroids are widely used and can be perceived by parents and patients to be safe, daily documentation of agents used and body surfaces exposed should be done during long-term treatment.

Conclusions:

Continuous use of moderate- to high-potency topical corticosteroids over several months can contribute to Cushing's syndrome. Growth and development as well as cortisol levels should be monitored in children on long-term topical corticosteroid treatment.

Antiallergic effect of the root of Paeonia lactiflora and its constituents paeoniflorin and paeonol

The root of Paeonia lactiflora PALL (PL, Family Paeoniaceae) has been used frequently as an antipyretic and anti-inflammatory agent in traditional medicines of Korea, China and Japan. To evaluate antiallergic effect of PL, we isolated its main constituents, paeoniflorin and paeonol, and evaluated in vivo their inhibitory effects against passive cutaenous anaphylaxis (PCA) reaction induced by IgE-antigen complex and scratching behaviors induced by compound 48/80. PL, paeoniflorin and paeonol potently inhibited PCA reaction and scratching behaviors in mice. Paeoniflorin exhibited the most potent inhibition against scratching behaviors and the acetic acid-induced writhing syndrome in mice. Paeonol most potently inhibited PCA reaction and mast cells degranulation. These findings suggest that PL can improve IgE-induced anaphylaxis and scratching behaviors, and may be due to the effect of its constituents, paeoniflorin and paeonol.

Inhibitory effect of schizandrin on passive cutaneous anaphylaxis reaction and scratching behaviors in mice

To evaluate the antiallergic effect of the fruit of Schizandra chinensis Baill (Family Magnoliaceae), which inhibited the mouse passive cutaneous anaphylaxis (PCA) reaction in a preliminary experiment, its main constituent, schizandrin, was isolated and its antiallergic effect investigated. Schizandrin inhibited the PCA reaction induced by the IgE-antigen complex, the scratching behaviors induced by compound 48/80 and the serum IgE production induced by ovalbumin. Schizandrin also inhibited the in vitro degranulation of compound 48/80-induced rat peritoneal mast cells and IgE-induced RBL 2H3 cells. Schizandrin reduced the protein expressions of TNF-alpha and IL-4 in IgE-induced RBL 2H3 cells. These findings suggest that schizandrin can improve IgE-induced anaphylaxis and scratching behaviors.

In Vitro and in Vivo Antiallergic Effect of the Fructus of Evodia rutaecarpa and Its Constituents

The unripe fruit of Evodia rutaecarpa (JUSS) BENTH (ER, Family Rutaceae) has been used frequently as a traditional medicine against inflammatory diseases in Korea, China and Japan. To evaluate antiallergic effect of ER, we isolated its main constituents, evodiamine and rutaecarpine, and evaluated in vivo their inhibitory effects against passive cutaneous anaphylaxis (PCA) reaction induced by IgE-antigen complex and scratching behaviors by compound 48/80. ER and its constituents, evodiamine and rutaecarpine, potently inhibited PCA reaction and scratching behaviors in mice, although ER weakly inhibited scratching behaviors. Evodiamine and rutaecarpine inhibited TNF-alpha and IL-4 protein expression in RBL-2H3 cells induced by IgE-antigen complex, although these did not inhibit degranulation of RBL-2H3 cells induced by IgE-antigen complex and rat peritoneal mast cells induced by compound 48/80. These findings suggest that ER and its constituents, evodiamine and rutaecarpine, may be effective for IgE-induced allergic diseases such as atopic dermatitis and rhinitis.

Inhibitory effect of ginsenoside Rg5 and its metabolite ginsenoside Rh3 in an oxazolone-induced mouse chronic dermatitis model

The effect of a main constituent ginsenoside Rg5 isolated from red ginseng and its metabolite ginsenoside Rh3 in a chronic dermatitis model was investigated. Ginsenosides Rg5 and Rh3 suppressed swelling of oxazolone-induced mouse ear contact dermatitis. These ginsenosides also reduced mRNA expressions of cyclooxygenase-2, interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma. The inhibition of ginsenoside Rh3 was more potent than that of ginsenoside Rg5. These findings suggest that ginsenoside Rh3 metabolized from ginsenoside Rg5 may improve chronic dermatitis or psoriasis by the regulation of IL-1beta and TNF-alpha produced by macrophage cells and of IFN-gamma produced by Th cells.

Lactic acid bacteria increase antiallergic effect ofArtemisia princeps pampanini SS-1

Artemisia princeps Pampanini, which is called Ssajuarissuk in Korean (SS-1), was fermented with lactic acid bacteria (LAB) and their passive cutaneous anaphylaxis reaction-inhibitory activity was investigated. Of these fermented agents, SS-1 extract fermented with Bifidobacterium infantis K-525 (F-SS-1) most effectively inhibited the release of P-hexosamindase from RBL-2H3 cells induced IgE. In IgE-induced RBL-2H3 cells, F-SS-1 inhibited proinflammatory cytokines IL-6 and TNF-alpha mRNA expression. Oral administration of SS-1 and F-SS-1 to mice inhibited passive cutaneous anaphylaxis (PCA) reaction induced by IgE and scratching behaviors induced by compound 48/80. The inhibitory activity of F-SS-1 against scratching behaviors was more effective than that of SS-1. These findings suggest that the fermentation of SS-1 with LAB can increase its antiallergic activity.

Methylprednisolone aceponate in eczema and other inflammatory skin disorders -- a clinical update

Methylprednisolone aceponate (MPA) has been shown to provide rapid, reliable and highly effective treatment of eczematous disorders, with an efficacy comparable to that of most reference topical corticosteroids. It also has excellent local and systemic tolerability. MPA is effective in the treatment of facial and scalp eczema and sunburn and has shown promising results in the treatment of psoriasis. Its rapid efficacy and lack of undesirable local and/or systemic side effects make MPA particularly suitable for use in children and infants. The wide range of formulations (0.1%) of MPA, including cream, ointment, fatty ointment, milk and solution, enable treatment to be tailored to the individual patient. In addition, MPA has the advantage of once-daily application compared with twice-daily treatment for other topical corticosteroids, thereby improving patient safety and promoting patient compliance but without compromising efficacy.

Effect of ginsenoside Rb1 and compound K in chronic oxazolone-induced mouse dermatitis

During the screening program to discover antipsoriatic agents from natural products, ginseng was found to show inhibitory activity in oxazolone-induced mouse ear dermatitis. Therefore, the effects of a main constituent ginsenoside Rb1 isolated from ginseng and its metabolite compound K on oxazolone-induced mouse ear dermatitis were investigated. Compound K at concentrations of 0.02% and 0.05% also potently suppressed mouse ear swelling by 54% and 76% at 16 days, respectively, although ginsenoside Rb1 did not significantly show the inhibitory activity. The compound K also significantly reduced the levels of mRNA of cyclooxygenase (COX)-2, IL-1beta, TNF-alpha, IFN-gamma and IL-4 increased in oxazolone-applied mouse ears. Based on these findings, the compound K may improve contact dermatitis or psoriasis by the regulation of COX-2 produced by macrophage cells and interferon-gamma and IL-4 induced by Th cells.

Effect of Chunghyuldan in Chronic Oxazolone-Induced Mouse Dermatitis

To evaluate the antipsoriatic effect of Chunghyuldan (CHD, Daio-Orengedokuto in Japanese), which exhibited anti-inflammatory and antiischemic actions, the inhibitory activity of CHD metabolized with and without human intestinal microflora was investigated in oxazolone-induced mouse ear dermatitis. The CHD and metabolized CHD (MCHD) at concentrations of 0.1% also potently suppressed mouse ear swelling by 52.7% and 63.2% at 16 d, respectively. The antipsoriatic effect between CHD and MCHD was not significantly different, although that of CHD weakly increased by the metabolism of human intestinal microflora. Both CHD and MCHD also potently reduced the mRNA levels of cyclooxygenase (COX)-2, interferon (IFN)-gamma and IL-4 increased in oxazolone-applied mouse ears, but weakly inhibited that of IL-1beta and TNF-alpha. Based on these findings, CHD may improve contact dermatitis or psoriasis by the regulation of COX-2 produced by macrophage cells and IFN-gamma and IL-4 produced by Th cells.

[Topical corticosteroids]

Therapeutics in dermatology underwent complete change after the introduction of topical hydrocortisone in the Fifties. At the time, stronger derivatives than hydrocortisone were synthetised and the indications for topical corticosteroids were expanded. Around twenty different molecules, classified according to their strength, are currently available for prescription in France. Many inflammatory or tumoral skin diseases respond to these products. The choice of a topical corticosteroid (strength, vehicle.) and of its mode of application (technique, rhythm of application) is oriented by the context (dermatitis treated, localization) and must respect "Good clinical practice" guidelines so as to select the best benefit/risk ratio.

Glucocorticoids mediate differential anti-apoptotic effects in human fibroblasts and keratinocytes via sphingosine-1-phosphate formation

Glucocorticoids are potent anti-inflammatory and immunomodulatory drugs which also induce growth inhibition in a variety of cell types. For this reason long-term treatment of inflammatory skin diseases may result in irreversible skin atrophy. To elucidate whether the antiproliferative action of glucocorticoids in fibroblasts is accompanied by induction of apoptosis we investigated the influence of dexamethasone (DEX) on both parameters. Interestingly, we revealed that growth inhibitory concentrations of this glucocorticoid did not induce fibroblast apoptosis. Moreover, DEX protected these cells from apoptosis induced by tumor necrosis factor alpha (TNFalpha)/actinomycin, UV-irradiation, and cell permeable ceramides. These findings are in contrast to the lack of anti-apoptotic effects detected in keratinocytes. Although DEX inhibited TNFalpha mediated nuclear factor-kappa (NF-kappaB) activity in fibroblasts, this mechanism was not involved in its cytoprotection as it was verified by specific NF-kappaB inhibitors. Therefore, we looked for alternative intracellular mediators. Coincubation of fibroblasts with the sphingosine kinase inhibitor N,N-dimethylsphingosine, which blocks formation of the sphingolipid degradation product sphingosine-1-phosphate (S1P), abrogated the protective glucocorticoid effect almost completely. As preincubation with S1P reduced the number of apoptotic cells after stimulation with TNFalpha/actinomycin and moreover DEX increased the intracellular S1P content a role of this sphingolipid in the cytoprotection by DEX is suggested.

Effects of FK506 (tacrolimus hydrate) on chronic oxazolone-induced dermatitis in rats

Chronic allergic contact dermatitis was induced in rat ear by repeated application of oxazolone. This dermatitis was accompanied by sustained ear swelling and marked epidermal hyperplasia. In the induced ear, there was marked inflammatory cell infiltration into the dermis site and the interferon-gamma amount increased in both protein and mRNA, while the interleukin-4 amount changed minimally. Topical administration of FK506 (tacrolimus hydrate) dramatically suppressed ear swelling and epidermal hyperplasia as well as the increase in interferon-gamma expression. Betamethasone valerate also showed suppressive effects, but 1,25-dihydroxyvitamin D(3) (calcitriol) had no effect. These results suggest that interferon-gamma plays an important role in dermatitis and this model could be a useful pharmacological model for chronic dermatitis featuring epidermal hyperplasia in which interferon-gamma plays a crucial role, such as psoriasis. FK506 demonstrating suppressive effects as potent as those of betamethasone valerate shows potential as a topically usable drug for such skin disorders.

Treatment of psoriasis. Part 1. Topical therapy and phototherapy

New developments in the topical therapy and phototherapy of psoriasis have greatly improved our ability to safely and effectively treat this debilitating disease. Topical corticosteroids remain the most commonly prescribed agents for psoriasis, but they are frequently prescribed with other agents. Investigations of corticosteroids claiming an improved benefit/risk ratio have yielded promising results, but more work is needed. Use of anthralin and tar has declined with the availability of the noncorticosteroids calcipotriene and tazarotene. Other experimental topical therapies are in various stages of development. Broadband ultraviolet B (UVB) remains the most commonly used phototherapy light source, but many patients are being treated with a new form of ultraviolet light, narrowband UVB. Although PUVA remains one of the most effective psoriasis treatments, its use is declining because of its association with cutaneous malignancies. New radiation sources such as lasers have been added to our armamentarium of available therapies and even newer light source-based treatments are being examined.

LEARNING OBJECTIVE

At the conclusion of this learning activity, participants should be familiar with the varying topical treatments for psoriasis as well as the different modalities of phototherapy. Participants should also have a better understanding of side effects associated with each treatment, which should help in determining options for therapy.

A pilot study to determine the effect of tazarotene gel 0.1% on steroid-induced epidermal atrophy

BACKGROUND

Repeated applications of a corticosteroid can induce epidermal atrophy. This study was performed to investigate whether the adjunctive use of tazarotene gel 0.1% might help to minimize the development of steroid-induced epidermal atrophy.

METHODS

Each of 24 healthy volunteers received the following six treatments (applied 6 days per week for 4 weeks), which were randomized to each of six sites on their forearms: no treatment, tazarotene vehicle, tazarotene vehicle + tazarotene gel 0.1%, diflorasone diacetate 0.05% ointment, diflorasone diacetate 0.05% ointment + tazarotene vehicle, or diflorasone diacetate 0.05% ointment + tazarotene gel 0.1%.

RESULTS

The mean epidermal thickness was increased by 20% (NS) and 62% (P < or = 0.0005) after applications of tazarotene vehicle and tazarotene gel 0.1%, respectively. Application of diflorasone diacetate reduced the mean epidermal thickness by 43% (P < or = 0.0005). Concomitant application of tazarotene gel 0.1% with diflorasone diacetate did not entirely prevent atrophy, but was shown to ameliorate 37% of the epidermal atrophy induced by diflorasone diacetate alone (P < or = 0.003 compared with steroid monotherapy).

CONCLUSIONS

Tazarotene gel 0.1% significantly reduces epidermal atrophy induced by diflorasone diacetate 0.05% ointment.

Tacrolimus suppressed the production of cytokines involved in atopic dermatitis by direct stimulation of human PBMC system. (Comparison with steroids)

Tacrolimus (FK506) ointment showed remarkable efficacy against atopic dermatitis in animal models and clinical trials. The suppressive effect of tacrolimus on the production of the cytokines involved in atopic dermatitis (IL-2, IL-3, IL-4, IL-5, IFN-gamma and GM-CSF) from human peripheral blood mononuclear cells (PBMC) was investigated. We constructed a new cytokine production system in which T cells are activated by direct stimulation in vitro with anti-CD3/CD2 or anti-CD3/CD28 antibody combination. Tacrolimus inhibited the production of these cytokines by both stimulations. In a comparative study with steroids (alclometasone dipropionate and betamethason valerate) in anti-CD3/CD2 system, tacrolimus and both steroids inhibited Th1 cytokines (IL-2, IFN-gamma), Th2 cytokines (IL-4, IL-5) and IL-3, GM-CSF (produced by both Th1 and Th2). The suppressive effect of tacrolimus on cytokine production was stronger than that of alclometasone dipropionate and equal to or stronger than that of betamethason valerate. The effective dose of tacrolimus (IC50, 0.02-0.11 ng/ml) is almost the same as for Th1 and Th2 cytokines, and 1 ng/ml of tacrolimus suppressed all cytokines completely. These results suggest that tacrolimus suppresses the allergic cytokines from T cells, and that tacrolimus ointment is effective against atopic dermatitis through the inhibition of cytokine production.

New approaches to topical therapy

Despite the rapid and proven efficacy of topical corticosteroids, side-effects can limit their clinical usefulness. Topically active macrolide immunosuppressants such as ascomycin and tacrolimus appear to provide comparable therapeutic potency without significant local or adverse effects. Data from ongoing studies will be crucial in determining the safety of these agents in the long term, and also their place within the current therapeutic armamentarium available for patients with atopic dermatitis. Enzyme inhibitors of PLA(2) and PDE 4 currently in the very early stages of clinical development also show potential promise as additional alternative strategies to topical treatment and may perhaps act as steroid sparing agents. Having been in the therapeutic doldrums for years, topical management of atopic dermatitis is likely to show great changes in the very near future.

Prednicarbate versus conventional topical glucocorticoids: pharmacodynamic characterization in vitro

PURPOSE

Pharmacodynamic characterization of topical glucocorticoids as prednicarbate (PC), its metabolites prednisolone 17-ethylcarbonate (PEC) and prednisolone (PD), betamethasone 17-valerate (BMV), betamethasone (BM) and desoximetasone (DM) by evaluating their effects on epidermal and dermal cells. Synopsis of pharmacokinetic and pharmacodynamic studies, possibly explaining the improved benefit-risk ratio of prednicarbate.

METHODS

Isolated foreskin keratinocytes were used to investigate the influence on epidermal inflammatory processes, dermal fibroblasts of the same origin to study antiproliferative activities of glucocorticoids. Interleukins were measured by ELISA-assay, the influence on II-1 alpha-production also on mRNA-level by RNAse protection assay. Proliferation was assessed by 3H thymidine incorporation and biodegradation by HPLC/UV-absorption. Cell viability was controlled by MTT assay.

RESULTS

In keratinocytes, inflammation was induced by TNF alpha, resulting in an increased II-1 alpha synthesis. This cytokine was particularly suppressed by PC and BMV, whereas PEC, PD, DM and BM were less potent (p < or = 0.05). Since, however, the double ester PC is rapidly degraded in keratinocytes, a RNAse-protection assay of II-1 alpha mRNA was performed allowing short incubation times and thus minimizing biodegradation effects. In agreement with the previous experiment, the antiinflammatory potency of native PC was confirmed. In fibroblasts, II-1 alpha and II-6 synthesis indicate proliferation and inflammation respectively. Whereas PC inhibited II-1 alpha and II-6 production in fibroblasts to a minor extent only, it was strongly reduced by the conventional glucocorticoids and PEC (p < or = 0.05). The minor unwanted effect of PC on fibroblasts was also reflected by its low influence on cell proliferation as assayed by 3H thymidine incorporation. More pronounced antiproliferative features were observed with BM, PEC and especially BMV.

CONCLUSIONS

Correlating antiphlogistic effects in keratinocytes (suppression of II-1 alpha) with antiproliferative effects in fibroblasts (suppression of II-1 alpha and II-6), the improved benefit-risk ratio of PC compared to conventional glucocorticoids does not result only from distinct drug metabolism in the skin but also from a specific influence on the cytokine network.

Prednicarbate biotransformation in human foreskin keratinocytes and fibroblasts

PURPOSE

Evaluation of skin layer-specific prednicarbate (PC) biotransformation, possibly explaining the improved benefit/risk ratio of this topical corticosteroid in atopic dermatitis (1,2).

METHODS

Metabolism of PC in keratinocyte and fibroblast monolayers derived from human juvenile foreskin was evaluated. Drug concentration was determined by HPLC/UV-absorption. Accompanying cell viability tests (MTT-tests) were performed to exclude toxic drug effects.

RESULTS

Keratinocytes hydrolyzed the double ester PC (2.5 x 10(-5) M) at position 21 to the monoester prednisolone 17-ethylcarbonate (P17EC) which nonenzymatically transformed to prednisolone 21-ethylcarbonate (P21EC). This metabolite was enzymatically cleaved to prednisolone (PD), the main biotransformation product at 24 hours. Fibroblasts, however, showed a distinctively lower enzyme activity. Both, PC and P17EC (or rather P21EC) were hydrolyzed to a minor extent only. The biotransformation pathway, however, was the same. When P17EC was added separately, it transformed to P21EC and again was cleaved by keratinocytes to a much higher extent. Despite of the rather high glucocorticoid concentration MTT-tests proved a non-disturbed cell viability and proliferation rate.

CONCLUSIONS

Extrapolating our results to the in-vivo situation, topically applied PC may be metabolized by epidermal cells during skin penetration. A complex mixture of compounds reaches the dermis, whose fibroblasts are barely able to metabolize the steroids. Since skin atrophy is less pronounced with PC as compared to conventional halogenated glucocorticoids, less potent PC metabolites appear to be the dominant species in the dermis.